Commonly-owned application Ser. No. 28,650 filed Mar. 20, 1987, discloses a collimator and S.P.E.C.T. (single photon emission computerized tomography) scintillation camera system in which there is one and only one focal point and in which that focal point is located inside the body of interest. The imaging process there described proceeds by moving the focal point over the area to be imaged. The entire disclosure of this application is hereby incorporated herein as if fully set forth.
The collimator there disclosed is circular (in the transaxial plane). This is disadvantageous when imaging a patient, because the interior region of the collimator must be large enough to permit the focal point to be traced over all points of the patient's body without collisions between the patient and the inner surface of the collimator. As a result, sensitivity decreases because of the large overall distance between the patient and the inner surface of the collimator.
It would be advantageous to provide a collimator of this type which would have improved sensitivity.